The present invention is directed to a vehicle rearview mirror system and, in particular, to an electro-optic rearview mirror system having vehicle heading sensing capabilities.
Electro-optic mirror systems typically include an electro-optic reflective element, such as an electrochromic reflective element, a liquid crystal element, or the like, and a circuit assembly for establishing a reflectance level of the reflective element. The circuit assembly may, conveniently, be mounted for movement with the reflective element which is moveable to be adjusted to a position convenient to the driver.
Vehicle heading sensing uses a heading sensor, such as a two-axis compass sensor, to sense the earth's magnetic field. The heading sensor functions best if it is mounted stationary with respect to the vehicle body. Therefore, it is common to mount the heading sensor on a circuit board that is separate from the circuit assembly that establishes the reflectance level of the reflective element and electrically connected therewith, such as by an electrical cable.